The cost of misfuelling your vehicle

10 April


How much does it cost when you put the wrong fuel in your vehicle?

Misfuelling a vehicle can be an expensive mistake... but not usually as expensive as it was for London businessman Toby Gawin.

Recently the Guardian reported how Mr Gawin had accidentally put petrol into a diesel hire car – and was charged £9,200 to pay for the damage.

Around 150,000 UK drivers of cars and vans put the wrong fuel every year. The vast majority put petrol into a diesel vehicle, because diesel nozzles are usually too large to fit in petrol filler holes.

What to do

If you realise you put the wrong fuel into your vehicle before you turn the ignition on, things are easy (and quite cheap) to fix. You simply drain and flush out the system. If you’re on a fuel forecourt with an attached workshop the most convenient solution is asking for their help.

If not, there are various organisations that can come to your aid. The AA has a Fuel Assist service that can do just that for a fraction of the price Mr Gawin faced. They claim to be able to fix minor misfuelling incidents within two hours. 

If, however, you turn on the engine, the wrong fuel is immediately pumped into lots of places it shouldn’t be… and that’s where the big bills can occur.

To maintain the warranty on the car for example, you may be forced to replace a long list of engine parts. The bill will run to several thousand pounds. A high performance engine could result in a bill of at least £10,000.

If, however, it’s your own vehicle, a garage could get you going for a fraction of that. The system can simply be cleaned through. At worst, the injectors may need replacing.

Mr Gawin had started his car and was charged for a full engine rebuild plus an engineer’s report on the misfuelled vehicle. After the Guardian contacted the car hire company, the hire company agreed to ‘discuss’ the bill with Mr Gawin.

At risk of misfuelling?

So what should companies do about the risk of misfuelling their vehicles? If you have both petrol and diesel vehicles and busy drivers who are always swapping vehicles then you are most at risk.

Firstly, a strong prominent labelling system should be followed. Every fuel cap should have an attention-grabbing sign displaying its fuel type.

Then there are physical devices available that can prevent misfuelling. A special fuel cap can prevent petrol pumps being put into a diesel car. These typically cost around £40 each.

A few insurance companies include misfuelling in their comprehensive cover. Some charge a little extra for this cover but most exclude it. It’s worth checking with your insurers.

Finally, consider a specific insurance cover like the AA Fuel Assist service. With this service, the AA will charge you a fee of around £200 for each call out. It’s quick, expert and convenient but it’s not a price any business want to pay frequently. Note that the AA fee doesn’t cover any replacement parts or engine rebuilding that may be necessary. 

Protect yourself

You can add the AA's Fuel Assist service to your Allstar fuel cards - on as many or as few of your fuel cards as you like. To add this service to your Allstar card or find out more, visit our website.

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